OptionMonster's tracking systems detected the purchase of 9,000 August 47 calls in one print yesterday for $1.20. The volume was above the strike's previous open interest, so this is clearly a new position.

Calls cheaply lock in where the stock can be purchased no matter how far it might rise. They can also generate significant leverage from relatively small moves in the share price.

Cashin: Japan Is Playing a 'Dangerous Game'

Monetary policy in Japan could trump news from the Fed this week, and the kind of inflation the Bank of Japan is creating - with little or no velocity - is a "dangerous game", said Art Cashin, UBS Financial Services director of floor operations.

The fund ended the session up 1.19 percent to $44.28 yesterday. The exchange-traded fund, which tracks Japanese stocks while adjusting for currency fluctuations, shot up from under $32 to above $52 between November and May but then pulled back as the broader market retreated.

More than 38,000 options traded in the fund yesterday, well above its daily average of 25,642 in the last month. Calls outnumbered puts by more than 5 to 1.